Simplify the tag used when logging

Drop the runcron/ prefix in the syslog tag.

runcron.c

@@ -767,10 +767,7 @@ int main(int argc, char **argv) {
   if (job_name == NULL) {
     job_name = basename(argv[optind]);
   }
-  if (asprintf(&log_tag, "runcron/%s", job_name) < 0) {
-    fprintf(stderr, "Error: could not allocate memory\n");
-    exit(2);
-  }
+  log_tag = job_name;
   if (log_to_syslog) {
     openlog(log_tag, LOG_PID, LOG_CRON);
   }
@@ -788,6 +785,5 @@ int main(int argc, char **argv) {
     export_metrics(r);
   }
 
-  free(log_tag);
   return r;
 }